The Central Blood Register (CBR) is a voluntary register for people willing to donate Rhesus Negative blood in the event of an emergency. The CBR aims to help coordinate between the demand, donors and the Thai Red Cross blood bank. Any hospital, organization or individual can approach the CBR 24 hours per day, 7 days a week.

Rhesus Negative (Rh-) blood is very rare among Thai people so the Thai Red Cross Blood Bank sometimes does not have adequate stores of Rh- blood when it is urgently needed. The Central Blood Register is a resource for Embassies, other hospitals, the Thai Red Cross and individuals to call when Rh- blood is needed. Calls can then be made to the volunteers on the list to look for an eligible and available donor. Registered donors can be removed from the list at any time.